Ultrasonic scanning of the human body for diagnostic purposes has been widely used in the medical community. Typically, an ultrasonic transducer which generates ultrasonic waves is passed over a certain portion of the body. The waves are transmitted through the body and then reflected back to the transducer. These waves differ depending upon the density of a particular body tissue. The waves reflected back to the transducer are then transmitted to the device for reconstructing the ultrasonic waves which are presented for continuous viewing or for the production of a permanent record.
However, problems have arisen in certain ultrasonic scans due to poor resolution of the produced ultrasonic pictures. Some of these problems have been alleviated by placing the ultrasonic transducer in a fluid media which is then placed in contact with the patient's skins. These devices have proved effective in producing high resolution ultrasonic scans of body tissues in close proximity of the skin but are less effective for deeper tissues or body cavities.
U.S. Pat. No. 3,779,234 issued to Eggleton et al tried to provide good resolution for an ultrasonic scan of the heart by providing a transducer within a catheter provided in the heart. A balloon is provided around this catheter which is filled with a fluid to provide adequate resolution. It should be noted however, that the balloon does not enlarge sufficiently to cover the entire heart chamber and that the ultrasonic transducer must be placed within the organ to be studied. U.S. Pat. No. 3,938,502 issued to Bom also is directed to a catheter for providing an ultrasonic scan of an interior body organ, such as the heart, but makes no provision for producing a high resolution scan by injecting a fluid at, or near, to the ultrasonic transducer.
Therefore, although the prior art shows the use of improving ultrasonic scan resolution by injecting a fluid around a transducer, a device is needed to improve the resolution further by injecting fluid within a body cavity and utilizing an ultrasonic transducer placed over the portion of the scanned organ, but not directly within the organ.